buffalo fly Haematobia exigua. The African dung beetles are well adapted to cattle faeces and
compete with fly larvae for food. Furthermore, the rapid burial of dung by the beetles reduces
the breeding habitats for the flies [ 21 ]. The scarab beetle (Scarabaeus sacer), also referred to
as sacred scarab among ancient Egyptians, was famous for its habit of rolling balls of dung
along the ground depositing them in its burrows. The female would lay her eggs in the ball
of dung. When they hatched, the larvae would use the ball for food. When the dung was con‐
sumed, the young beetles would emerge from the hole [ 24 ]. Dung beetles have been reported
to reduce horn flies by as much as 95%, bush flies by 80–100% and result in nine times of fewer
parasites produced [ 25 , 26 ]. Dung beetles can also play a role in the biocontrol of bovine gas‐
trointestinal nematodes (Trichostrongylidae). The spotted lady beetle (Coleomegilla maculata)
is also able to feed on the eggs and larvae of the Colorado potato beetle Leptinotarsa decemlin‐
eata [ 27 ] and can be used in its control. The larvae of Coccinellids (ladybird or ladybug) are
voracious predators of aphids and also consume mites, scale insects and small caterpillars.
5.1.1.6. Dragonflies and water bugs
Dragonflies (see Figure 1 ) may look like scary biters, but they are only dangerous to mosqui‐
toes. Dragonfly larvae, “nymphs”, feed on mosquito larvae, and adult dragonflies feed on
adult mosquitoes [ 28 ]. On the other hand, water bugs, Diplonychus indicus, are also known to
prey on mosquito larvae [ 29 ].
5.1.2. Vertebrates
5.1.2.1. Amphibians and fishes
The water tortoise Pelomedusa subrufa has been reported to be able to remove ticks from black
rhinos in a streambed [ 30 ]. Also in some areas, the mosquito larvae may be controlled biologi‐
cally by predatory fish such as Gambusia affinis and Guppy poecilia [ 31 ]. One study showed that
introducing Gambusia affinis into water wells resulted in 98% reduction in the larval density of
Anopheles stephensi [ 32 ]. Other predatory fishes such as the Cyprinus carpio, Ctenopharyngodon
idella, Aphanius dispar, Aplocheilus blocki, Tilapia spp., Catla catla, Labeo rohita and Cirrhinus mrigala
have also shown promise in the control of mosquitoes [ 33 ]. In China, for example, the presence
of carp fish in certain rice fields reduced the number of malaria cases [ 34 ]. Another predatory
fish, the black carp (Mylopharyngodon piceus), has shown promise in the biocontrol of the inter‐
mediate host snails of fish‐borne zoonotic trematodes [ 35 ]. Snails (some of which are intermedi‐
ate hosts of fascioliasis, paramphistomes and schistosomes) are eaten by some fishes as well.
5.1.2.2. Reptilians
Some lizards can eat arthropods. The lizard stomach may contain as many as 2.5–15 ticks/
stomach. However, because there are few lizards near the bird nest, their effect on the tick
population may be limited [ 21 ]. The Australian gecko Gehydra dubia and the exotic Asian
house gecko Hemidactylus frenatus have been observed to prey on mosquitoes; in the labora‐
tory, they have been observed to prey more on female mosquitoes and are therefore a promis‐
ing tool for the biological control of malaria [ 28 ].
Biological Control of Parasites
http://dx.doi.org/10.5772/6801229